Reversible ratchet type wrench



Feb, g, 3962 T. ca. HARE 3,919,682

REVERSIBLE RATCHET TYPE WRENCH Filed April 8, 1960 2 Sheets-Sheet 1INVENTOR. 3 TERENCE 6. HARE ATTORNEY Feb. 6, 1962 T. G. HARE 3,@19,682

REVERSIBLE RATCHEIT TYRE WRENCH Filed April 8, 1960 2 Sheets-Sheet 2 INVEN TOR. Ensues G. HA

ATTORNE Y5 United States Patent ()fifice Edilhgdb? Patented Feb. 6, 19623,019,682 REVERSIBLE RATCHET TYPE WRENCH Terence G. Hare, 17638 GrandRiver, Detroit, Mich. Filed Apr. 8, 1960, Ser. No. 20,924 3 Claims. (Cl.81--63.2)

This invention relates to manually operated wrenches and particularly towrenches having reversible ratchet mechanisms.

in manually operated wrenches having reversible ratchet mechanisms it isdesirable that the ratchet mechanisms be of such construction that theywill operate with a minimum of maintenance to permit the tightening orloosening of a workpiece such as a nut. in addition, the constructionshould be such that the wrench is positively locked in tightening orloosening position and yet is easily changed from one position toanother.

In my copending application Serial No. 683,772, filed September 13,1957, titled Reversible Ratchet Type Wrench, now Patent No. 2,957,377,issued October 25, 1960, of which this application is acontinuation-in-part, there is disclosed and claimed a reversibleratchet wrench which comprises a body having a head and a handle. Acircular member having ratchet teeth on the periphery thereof isjournalled for rotation in the head. A pawl with ratchet teeth along oneedge is positioned in a cavity in the head which opens to the peripheryof. the rotatable member. The pawl has a pair of side Walls which engagethe side walls of the cavity to limit the movement of the pawl in onedirection or the other. are provided which bias the pawl so that ittends to move in a direction toward the rotatable member. The pawl isshiftable in the cavity circumferentially of the rotatable member inopposite directions as limited by intcrengagement by the side walls ofthe pawl and the side walls of the cavity. In addition, the pawl isshiftable in the cavity in a direction radially of the rotatable memberto permit a ratcheting action.

It is an object of this invention to provide an improved reversibleratchet wrench of the type shown in the aforesaid application Serial No.683,772.

It is a further object of this invention to provide such a wrench whichincludes a novel mechanism for reversing the operation thereof. 1

In the drawings:

FIG. 1 is a sectional view on an enlarged scale of a portion of a wrenchembodying the invention.

FIG. 2 is a fragmentary part-sectional plan view taken along the line 22in FIG. 1.

FIG. 3 is a fragmentary part-sectional plan view sirnilar to FIG. 2showing the parts in a different position.

FIG. 4 is a view similar to FIG. 3 showing the parts in a stilldifferent position.

FIG. 5 is a part sectional fragmentary elevation of a further modifiedform of wrench.

FIG. 6 is a part sectional plan View of the wrench shown in FIG. 5.

A form of wrench embodying the invention is shown in FIGS. l4 andcomprises a body 10 having a handle 11 and a head 12. Head 12 is formedwith a cylindrical opening 13 in which a cylindrical rotatable member 14is journalled. Cylindrical member 14 is formed with a plurality ofratchet teeth 15 along the periphery thereof. The engagement of theteeth 15 with the sides of the opening 13 journals the cylindricalmember 14 in the opening 13. Head 12 includes a bottom Wall 16 which hasan opening 17 through which a cylindrical projection 18 which isintegral with member 14 extends. The periphery of projection 13 isformed with a groove 19 in which an O-ring 21 is seated for engagementwith the Walls of the opening 17 to provide a dirt and oil seal. Thelower end Spring means of the projection 18 is formed with a well-knowntype of disconnectable connection with various work-engaging memberssuch as socket wrenches and the like.

Referring to FIGS. 1 and 2, body 12 is provided with a wedge-shapedcavity 21 which communicates with the periphery of the cylindricalmember 14. Cavity 21 has converging straight sides 22, 23 which divergein the direction of the periphery of the cylindrical member 143. Awedge-shaped pawl 24 is positioned in cavity 21 for limited floatingmovement as presently described. Pawl 24 includes an arcuate row ofteeth 25 adjacent teeth 15 of cylindrical member 14 adapted tointerengage said teeth 15. Pawl 24 also includes converging sides 26, 27which are adapted to contact the sides 22, 23 of cavity 21 and therebylimit the circumferential movement of pawl 24. The sides 26, 27 of thepawl diverge in a direction toward the teeth 25 of the pawl.

A pin 23 is rotatably mounted in an opening 29 in the body 1d whichopening has its axis parallel to the axis of rotation of the cylindricalmember 14. A passageway 29:: provides communication between cavity 21and opening 29. A tightly wound helical coil spring 36} is positionedbetween pawl 24 and pin 28. The ends or" the spring extend into openings31, 32 in the pawl 24 and pin 28, respectively.

Pin 28 is provided with a reduced portion 33 intermediate its ends andis held in position in opening 29 by a C-shaped collar 34 which has agreater diameter than the diameter of the opening 29 and is compressedor sprung inwardly around the reduced portion 33 to frictionally holdthe pin 23 in the opening 29. Pin 28 is adapted to be shifted or rotatedbetween two positions for shifting the pawl as presently described. Inorder to facilitate the rotation of the pin, a shifting lever 35 isprovided on the upper end of pin 28 externally of the body it}. Thelever 35 and, in turn, the pin 28 are held in their adjusted position byengagement with bosses 36, 37 and by a spring loaded ball 38 that isyieldingly urged upwardly by a spring 39 to hold the shifting lever 35against either the boss 36 or boss 37.

The relationship of the angles of the teeth 15, 25 is substantially thesame as described in the aforementioned application Serial No. 683,772so that with the lever 35 in one position pawl 24 is positioned incavity 21 with one of its surfaces in parallelism and contact with anadjacent surface of the cavity 21. As the handle 11 of the wrench isrotated, the pawl is wedged by the action of the teeth and by contactwith the adjacent surfaces of the pawl and cavity to prevent movement ofthe pawl and thereby cause the rotatable member 14 to rotate. A reverserotation of the handle 11 of the wrench provides a ready ratcheting ofthe pawl over the teeth of the rotatable member 14. As shown in FIG. 2,the spring 3i) is bent out of its normal straight condition and thustends to urge the pawl toward surface 23 and in turn in wedgingrelation.

When the shifting lever 35 is shifted, the direction of the axis of theopening 32 in the pin 38 is rotated thereby tending to shift the axis ofthe spring 3%}. As shown in FIGS. 1 and 2, an upwardly extending pin 4bis provided on the pawl 24 and extends upwardly into a V-shaped slot 41in the top wall 42 of the wrench. The top wall 42 comprises a separatemember that is held in position to cover the opening 13 and cavity 21 asby staking as shown at 43.

The relationship of the pin 48 to the slot 41 is such that during thenormal ratcheting action of the pawl the pin it) and slot 41 do notaffect the action of the pawl but during the shifting of the pawl inorder to reverse the rotation of the wrench, the pin engages the sidesof the slot to positively insure the shifting of the pawl.

Specifically, when the shifting lever 35 is moved from the positionshown in FIG. 2 to the position shown in FIG. 3, the spring is distortedforcing the pin 40 to engage the side wall 44 of the slot 41. Since thespring 39 tends to straighten out, the spring causes the pawl to ride upthe wall 44 and radially outwardly away from the cylindrical member 14onto the other side wall 45 of the slot. As shown in FIG. 4, the pawl isthen free to move into wedging relationship with the surface 22 of thecavity 21 or to ratchet out of engagement in the normal fashion ofoperation of the wrench.

When the shift lever 35 is returned to the position shown in FIG. 2, thepin 49 is caused by the bending or distortion of the spring 35! toengage the side wall 45 of the slot 41 and ride up the side wall 45thereby moving the pawl radially away from the rotatable member 14 anddisengaging the teeth of the pawl from the teeth of the rotatable memberand thereafter down the side wall 4-4.

The length of the legs of slot 41 is such that the pin it) does notcontact the ends of the slot at any time.

It can thus be seen that the pin 40 and slot 41 operate only during theshifting of the pawl to insure the disengagement of the teeth of thepawl from the teeth of the rotatable member. Such action is preferred ininstances where dirt, grime and the like may have entered the interiorof the wrench and might tend to interfere with the shifting of the pawlbut not necessarily with the racheting action of the pawl.

A modified form of wrench embodying the invention is shown in FIGS. 5and 6 wherein the pin 40 and slot 41, which operate during the shiftingof the pawl, are rep'laced by a different structure. In all otherrespects, the wrench shown in FIGS. 5 and 6 is identical to the wrenchshown in FIGS. 1-4 and for purposes of clarity identical referencenumerals have been used to describe the wrench. As shown in N68. 5 and6, the rotatable member 14 is provided with a peripheral groove asintermediate the upper and lower ends thereof. A tightly wound endlessspring 47 is positioned in the peripheral groove 46. The outer diameterof the spring 47 in the untensioned state is greater than the outerdiameter of the circle formed by the apexes of the teeth 15 on therotatable member 14 so that when the spring 4-7 is in position in groove46 and the rotatable member 14 is within the head 12 a portion of thespring 47 is always pushed or bulged outwardly in the space between thepawl 24 and the sides 22, 23, as the case may be. When the shiftinglever 35 is shifted, tending to shift the axis of the spring 30, a forceis placed on the pawl 24 tending to eliminate the bulge in therspring47. This forces the pawl 24 away from the teeth 15 on a rotatable member14 so that the bulge between the pawl 24 and one side of the cavity 21is eliminated and a bulge in. the spring is provided between the pawl 24and the other side of the cavity 21. In this manner, a positive movementof the pawl away from the rotatable member is insured during theshifting. In normal operation of the pawl, the spring 47 does not affectthe ratcheting of the pawl.

In both forms of the invention, a ready ratcheting action is provided.The reversing mechanism can be ctuated when the wrench is under torquewithout dam;- aging the wrench. If the reversing action is actuated whenthe wrench is under torque the pawl will shift when the torque isrelieved. In both forms of the invention, the torque is transmittedthrough the rotatable member to the head of the wrench by contact of theteeth on the rotatable member with the inner surface of the opening inthe head in which the rotatable member is positioned.

The torque is not only transmitted through the pawl in each of the formsof the invention but, in addition, from the head to the rotatable memberbecause of the bearing action of the head on the teeth of the rotatablemember and the opening in the head through which the to facilitate thisaction, the apexes of the teeth on the periphery of the rotatable memberare flattened as shown in FIGS. 1-6.

In order to further facilitate the bearing action between the head andthe rotatable member, the tolerance between the periphery of the head,that is, the apexes of the teeth, and the interior opening in the headis less than the tolerance between the projection on the rotatablemember and the opening in the head through which the projection extends.In this manner, the 0-ring permits a slight lateral movement of therotatable member as may be needed to provide the bearing action withoutbinding of the projection in the opening. For example, in the form ofthe invention shown in FIG. 1, the tolerance between the periphery ofthe rotatable member 14- and the cylindrical opening 1'3 is less thanthe tolerance between the cylindrical projection 18 and the opening 17,the 0-ring 2t? taking up the difierence in tolerance so that aneifective bearing action will occur between the teeth 2.5 and thesurface of the opening 13.

I claim:

1. In a wrench comprising a body having a head and a handle, a rotatablemember journalled for rotation in said head, said rotatable memberhaving ratchet teeth around the periphery thereof, said body having acavity therein opening to the periphery of said rotatable member, saidcavity having opposite side wall portions diverging in the direction ofthe periphery of said rotatable member, a pawl within said cavity havingalong one edge ratchet teeth engageable with the ratchet teeth on therotatable member and having a pair of side walls diverging in adirection toward said edge, said pawl being shiftable in said cavitycircumferentially of said rotatable member in opposite directions aslimited by interengagement of said side walls of the pawl and said sidewall portions of the cavity and being shiftable in said cavity in adirection radially of said rotatable member, and means biasing said pawlso that it tends to move in a direction toward said rotatable member,the improvement including means interengaging between said pawl and saidbody during the shifting movement of said pawl circumferentially toreverse the operation of said wrench, said means being operable duringsaid shifting to move said. pawl radially outwardly away from saidrotatable member, thereby insuring the disengagement of the teeth onsaid pawl from the teeth on said rotatable member.

2. In a wrench comprising a body having a head and a handle, a rotatablemember journalled in said head and having ratchet teeth on the peripherythereof, said body having a wedge-shaped cavity communicating with theperiphery of said rotatable member, a wedge-shaped pawl positioned insaid cavity, said pawl being formed with an arcuate row of teeth adaptedto engage the periphery of said rotatable member, each side of said pawlbeing adapted to engage a side of said cavity to limit thecircumferential movement of said pawl between a first extremecircumferential position to a second extreme circumferential position,and means for yieldingly urging said pawl toward the periphery of saidrotatable member and for selectively shifting said pawl between saidfirst and second extreme circumferential positions, whereby in eachcircumferential position the further circumferential movement of saidpawl in one direction is prevented by engagement of the side of saidpawl with the side of said cavity while circumferential movement in theopposite direction and radial movement is yieldingly resisted by saidlatter means, the improvement including means interengaging between saidpawl and said body during the shifting movement of said pawlcircumferentially to reverse the operation of said wrench, said meansbeing operable during said shifting to move said pawl radially outwardlyaway from said rotatable member, thereby insuring the disengagement ofthe teeth on said pawl from the teeth on said rotatable member.

3. In a wrench comprising a body having a head and a handle, a rotatablemember iournalled in said head and having ratchet teeth on the peripherythereof, said body having a wedge-shaped cavity communicating with theperiphery of said rotatable member, a wedge-shaped pawl positioned insaid cavity, said pawl being formed with an arcuate row of teeth adaptedto engage the periphery of said rotatable member, each side of said pawlbeing adapted to engage a side of said cavity to limit thecircumferential movement of said pawl between a first extremecircumferential position to a second extreme circumferential position,and means for yieldingly urging said pawl toward the periphery of saidrotatable member and shifting said pawl between said first and secondextreme circumferential positions comprising an abutment, a coil springcompressed between said pawl and said abutment, said abutment beingrotatable from a first position to a second position to shift the axisof the spring and in turn the pawl between one side and the other of theline extending between said abutment and the axis of rotation of saidrotatable member, the improvement which comprises interengaging meansbetween said pawl and said body adapted to positively guide the movementof said pawl radially outwardly away from said rotatable member duringthe shifting of the axis of the spring from one side to the other of aline extending between the abutment and the axis of rotation of therotatable memher.

4. The combination set forth in claim 3 wherein said interengaging meanscomprises a pin on said pawl, said body having a V-shaped slot the sidesof which diverge toward the periphery of said rotatable member, said pinbeing adapted to engage the sides of said slot to guide the movement ofthe pawl.

5. The combination set forth in claim 3 wherein said interengaging meanscomprises a pair of intersecting surfaces in said body diverging towardthe periphery of said rotatable member and the pawl being adapted toengage said surfaces during the shifting of said pawl from onecircumferential position to the other.

6. In a Wrench comprising a body having a head and a handle, a rotatablemember journalled in an opening in said head and having ratchet teeth onthe periphery thereof, a cover fixed on said body and closing theopening in said head, said body having a wedge-shaped cavitycommunicating with the periphery of said rotatable member, awedge-shaped pawl positioned in said cavity, said pawl being formed withan arcuate row of teeth adapted to engage the periphery of saidrotatable member, each side of said pawl being adapted to engage a sideof said cavity to limit the circumferential movement of said pawlbetween a first extreme circumferential position to a second extremecircumferential position, and means for yieldingly urging said pawltoward the periphery of said rotatable member and shifting said pawlbetween said first and second extreme circumferential positionscomprising an abutment, a coil spring compressed between said pawl andsaid abutment, said abutment being rotatable from a first position to asecond position to shift the axis of the spring and in turn the pawlbetween one side and the other of the line extending between saidabutment and the axis of rotation of said rotatable member, theimprovement which comprises interengaging means between said pawl andsaid cover adapted to positively guide the movement of said pawlradially outwardly away from said rotatable member during the shiftingof the axis of the spring from one side to the other of a line extendingbetween the abutment and the axis of rotation of the rotatable member.

7. The combination set forth in claim 6 wherein said interengaging meanscomprises a pin on said pawl, 21 vshaped slot in the underside of saidcover, the sides of said slot diverging toward the periphery of saidrotatable member, said pin being adapted to engage the sides of saidslot to guide the movement of the pawl.

8. In a wrench comprising a body having a head and a handle, a rotatablemember journalled in said head and having ratchet teeth on the peripherythereof, said body having a wedge-shaped cavity communicating with theperiphery of said rotatable member, a wedge-shaped pawl positioned insaid cavity, said pawl being formed with an arcuate row of teeth adaptedto engage the periphery of said rotatable member, each side of said pawlbeing adapted to engage a side of said cavity to limit thecircumferential movement of said pawl between a first extremecircumferential position to a second extreme circumferential position,and means for yieldingly urging said pawl toward the periphery of saidrotatable member and shifting said pawl between said first and secondextreme circumferential positions comprising an abutment, a coil springpositioned between said pawl and said abutment, said abutment beingrotatable from a first position to a second position to shift the axisof the spring and in turn the pawl between one side and the other of theline extending between said abutment and the axis of rotation of saidrotatable member, the improvement which comprises a circumferentialgroove in the periphery of said circular member, and an endless coilspring positioned in said groove, the outer diameter of said latterspring being greater than the diameter of said rotatable member wherebya portion of'said spring extends outwardly between the pawl and thewedge-shaped cavity in any adjusted position of said pawl, said latterportion acting to move said pawl radially outwardly away from saidrotatable member during the shifting of the axis of the spring from oneside to the other of a line extending between the abutment and the axisof rotation of the rotatable member.

References Cited in the file of this patent UNITED STATES PATENTS283,801 Miller Aug. 28, 1883 893,097 Reams July 14, 1908 1,179,341Spirikowicz Apr. 11, 1916 1,888,885 Pepperdine Nov. 22, 1932 2,126,843Tintera et a1. Aug. 16, 1938 2,735,324 Goldwater et a1 Feb. 21, 19562,758,493 Goldwater Aug. 14, 1956 2,869,410 Prichard Jan. 20, 1959

